Final Answer:
Community 2 is considered to have less biodiversity than community 1 even though both communities have four different species of trees because b) Community 2 has a lower number of tree species. So, Option B is correct.
Step-by-step explanation:
Community 2 is considered to have less biodiversity than Community 1 because it has a lower number of tree species. Biodiversity is not solely about the number of species present, but also about the distribution and evenness of those species within a community. In this case, although both communities have four different species of trees, Community 2 likely has a more uneven distribution of these species compared to Community 1.
Biodiversity is often measured not just by the number of species, but also by indices that take into account the abundance and distribution of each species. One such index is the Shannon Diversity Index (H'), which considers both species richness and evenness. If Community 2 has a lower value of H' compared to Community 1, it indicates a less even distribution of species, supporting the idea that Community 2 has less biodiversity despite having the same number of tree species.
Additionally, biodiversity encompasses more than just trees; it includes the variety of all living organisms in an ecosystem. If Community 2 has a lower number of tree species but a greater variety of other plant or animal species, it might still have comparable or even higher overall biodiversity than Community 1. However, the question specifically focuses on tree species, making the lower number of tree species in Community 2 the key factor in its perceived lower biodiversity.